Northland Regional Council engaged WM Group to carry out water balance modelling for Lake Waiparera, Lake Heather, Lake Rotoroa and Lake Ngatu in the Aupouri Pennisula and Lake Kahuparere in Pouto Pennisula. The water balance assessments were used to estimate lake flows and temporal changes in storage volumes for the purpose of lake water quality modelling to inform management plans for the restoration of habitat for native lake fauna and flora as well as the removal of pest populations. The water balance and hydrogeological assessments also provided valuable information on the nature of lake-groundwater interactions.
Bathymetric and lidar data was to develop topographic-bathymetric Digital Elevation maps that were used to construct hypsographic curves for the lakes to show the relationship between lake surface area and water depth in each lake. Simple spreedsheets were used lake water balance modelling.